Predictors of radiotherapy outcome in patients with T2 supraglottic carcinoma.

The decision regarding treatment of early supraglottic carcinoma remains controversial. Single institution clinical data of patients with T2 supraglottic carcinoma treated exclusively with radiotherapy in terms of prognostic factors and treatment results were analyzed. Patient-related factors that would potentially by useful for optimal therapeutic decision to be undertaken were especially investigated. Between 1994 and 2004, 78 patients with T2 supraglottic carcinoma underwent radiotherapy (RT) in Maria Sklodowska-Curie Memorial Cancer Centre and Institute of Oncology, Gliwice Branch, Poland. There were 54 (69%) males and 24 (31%) females in the median age of 61 years. There were 17 (22%) patients with N+. Median body mass of patients before (BM0) and after RT (BM1) was 74 kg (range 45.2-130 kg) and 72.9 kg (range 49.9-122.5 kg), respectively. Median hemoglobin concentrations before (Hb0) and after (Hb1) RT were 14.3 and 13.4 g/dl, respectively. Median change of Hb concentration during RT (dHb) was -0.8 g/dl. All were treated up to total doses (TD) ranged from 62.5 to 72 Gy. The overall treatment time (OTT) ranged from 30 to 70 days. Estimates of local control (LC), ultimate local control (uLC), and overall survival (OS) were calculated using the Kaplan-Meier method. Log rank statistics, Cox proportional hazard model and step-wise Cox regression hazard model were employed to identify prognostic factors for LC, uLC, and OS in univariate and multivariate analyses. The 5-year LC, RC, uLC and OS rates were 85, 92, 88, and 56%, respectively. In multivariate analysis N+ (p = 0.01) and prolonged OTT (p = 0.03) significantly decreased LC. Females (p = 0.02), higher BM0 (p = 0.03), and HB0 (p = 0.006) significantly prolonged OS. Patient-related factors like gender, hemoglobin concentration, and body mass may predict treatment outcome. Radiotherapy is effective for T2 supraglottic carcinoma of the larynx unless higher dose intensity is provided. Involved regional lymph nodes significantly deteriorate locoregional cure.